CC,
First, let me say that I'm glad you are recovering and I hope you continue to do so...
I placed a trigger icon in case certain words may upset someone.

In a way you answered your own question. Perhaps you noticed that this type of depression feels different/has added to issues for which you are receiving treatment.

Whenever we are hospitalized for any reason, we are not in control of very much. Being seriously ill requires us to be in a place that is not know for being "user-friendly."
Treatment protocols cover many things--xrays, blood work, medication, perhaps other things--in order for our physician(s) to help us get well. Most likely we share a room with another patient...at a time when we may just want to be left alone.

Combine all these things and many, if not most, people will have some kind of depression during/after hospitalization.
Being at home is wonderful but we are still not well...recovery/regaining strength takes time. Just the fact that we were sick enough to be hospitalized is scary and depressing!

Be as kind to yourself as you can, CC. It stressed you mentally as well as physically. It's good that you recognized this and can address it with your therapist.
And please be patient with yourself...healing of any kind takes time.

My best wishes,
Cap